Effect of reservoir tillage on rainwater harvesting and soil erosion control under a developed rainfall simulator.

Soil erosion is a serious environmental threat in the Mediterranean region due to torrential rainfalls, and it contributes to the degradation of agricultural land. Techniques such as rainwater harvesting may improve soil water storage and increase agricultural productivity, which could result in more effective land usage. Reservoir tillage is an effective system of harvesting rainwater, but it has not been scientifically evaluated like other tillage systems. Its suitability for the conditions in Spain has not been determined. To investigate and quantify water storage from reservoir tillage and how it could be adapted to improve infiltration of harvested rainwater, a laboratory-scale rainfall simulator was developed. Rainfall characteristics, including rainfall intensity, spatial uniformity and raindrop size, confirm that natural rainfall conditions are simulated with sufficient accuracy. The simulator was auto-controlled by a solenoid valve and three pressure nozzles were used to spray water corresponding to five rainfall intensities ranging from 36 to 112 mm h-1 for 3 to 101-year return period with uniformity coefficients between 83 and 94%. In order to assess the reservoir tillage method under surface slopes of 0, 5, and 10%, three soil scooping devices with identical volume were used to make depressions in the following forms: a) truncated square pyramid, b) triangular prism, and c) truncated cone. These depressions were compared to a control soil surface with no depression. For the loam soil used in this study, results show that reservoir tillage was able to reduce soil erosion and surface runoff and significantly increase infiltration. There was significant difference between the depressions and the control. Compared to the control, depression (a) reduced surface runoff by about 61% and the sediment yield concentration by about 79%.

Direct and indirect economic impacts of drought in the agri-food sector in the Ebro River basin (Spain).

The economic evaluation of drought impacts is essential in order to define efficient and sustainable management and mitigation strategies. The aim of this study is to evaluate the economic impacts of a drought event on the agricultural sector and measure how they are transmitted from primary production to industrial output and related employment. We fit econometric models to determine the magnitude of the economic loss attributable to water storage. The direct impacts of drought on agricultural productivity are measured through a direct attribution model. Indirect impacts on agricultural employment and the agri-food industry are evaluated through a nested indirect attribution model. The transmission of water scarcity effects from agricultural production to macroeconomic variables is measured through chained elasticities. The models allow for differentiating the impacts deriving from water scarcity from other sources of economic losses. Results show that the importance of drought impacts are less relevant at the macroeconomic level, but are more significant for those activities directly dependent on water abstractions and precipitation. From a management perspective, implications of these findings are important to develop effective mitigation strategies to reduce drought risk exposure.

Effect of reservoir tillage on rainwater havesting and soil erosion control under a developed rainfall simulator

Soil erosion is a serious environmental threat in the Mediterranean region due to torrential rainfalls, and it contributes to the degradation of agricultural land. Techniques such as rainwater harvesting may improve soil water storage and increase agricultural productivity, which could result in more effective land usage. Reservoir tillage is an effective system of harvesting rainwater, but it has not been scientifically evaluated like other tillage systems. Its suitability for the conditions in Spain has not been determined. To investigate and quantify water storage from reservoir tillage and how it could be adapted to improve infiltration of harvested rainwater, a laboratory-scale rainfall simulator was developed. Rainfall characteristics, including rainfall intensity, spatial uniformity and raindrop size, confirm that natural rainfall conditions are simulated with sufficient accuracy. The simulator was auto-controlled by a solenoid valve and three pressure nozzles were used to spray water corresponding to five rainfall intensities ranging from 36 to 112 mm h− 1 for 3 to 101-year return period with uniformity coefficients between 83 and 94%. In order to assess the reservoir tillage method under surface slopes of 0, 5, and 10%, three soil scooping devices with identical volume were used to make depressions in the following forms: a) truncated square pyramid, b) triangular prism, and c) truncated cone. These depressions were compared to a control soil surface with no depression. For the loam soil used in this study, results show that reservoir tillage was able to reduce soil erosion and surface runoff and significantly increase infiltration. There was significant difference between the depressions and the control. Compared to the control, depression (a) reduced surface runoff by about 61% and the sediment yield concentration by about 79%.

Efeito da aplicação de composto orgânico sobre a qualidade do solo cultivado com cana-de-açúcar (Saccharum spp.)

A dinâmica ambiental possui capacidade limitada de reciclagem e a crescente utilização resíduos agroindustriais, especialmente na agricultura, pode levar a situações de poluição do solo e demais componentes ambientais. A manutenção da produtividade de ecossistemas agrícolas e naturais depende do processo de transformação da matéria orgânica e, por conseguinte, da biomassa microbiana do solo, e que é responsável pela decomposição e mineralização de resíduos no mesmo. A dinâmica natural dos microrganismos do solo, em constante mudança e adaptação, os torna um indicador sensível às mudanças resultantes de diferentes práticas de manejo agrícola. Sendo assim, conhecer essas alterações e suas interferências é fundamental para identificar estratégias adequadas de manejo, apontando técnicas de utilização adequadas. O objetivo deste trabalho foi avaliar a qualidade de um solo agrícola, cultivado com três variedades de cana-de-açúcar (Saccharum spp.), comparando a utilização de adubação mineral frente à utilização de fertilizante orgânico composto no período final de formação dos perfilhos (120 dias após o plantio). Foi implantado, em condições de campo, o cultivo de cana-de-açúcar (cana planta), utilizando as variedades RB 867515, RB 962869 e RB 855453, onde cada variedade foi cultivada de três formas distintas, sendo elas: plantio controle (CT) sem aplicação de insumos para adubação; plantio orgânico (OG) com aplicação de fertilizante orgânico; e plantio convencional (CV) com aplicação de adubação mineral, seguindo recomendações de adubação após análise química inicial do solo local. Cada parcela possuía 37 m2, com 5 sulcos de 5,0 m de comprimento e espaçamento de 1,5 m entrelinhas, sendo os três sulcos centrais formando a área útil. De acordo com a variedade e o tipo de adubação, foram formados nove tratamentos: T1 86CT, T2 96CT, T3 85CT, T4 6OG, T5 96OG, T6 85OG, T7 86CV, T8 96CV e T9 85CV, com delineamento estatístico de blocos ao acaso e quatro repetições. Os parâmetros químicos do solo analisados foram macronutrientes e micronutrientes; os parâmetros microbiológicos foram carbono da biomassa microbiana (CBM), respiração basal do solo (RBS), quociente metabólico (qCO2), número mais provável de fungos e bactérias do solo (NMP); e, por fim, a produtividade agrícola (t/ha). Os resultados foram submetidos a análise de variância (ANOVA) e à comparação das médias através do teste de Tukey (10%). Também foi realizada a análise de variância dos dados e correlação cofenética de Pearson para formação de dendogramas. Com base no período estudado, considerado como fase crítica da formação do canavial, concluiu-se que os parâmetros químicos que evidenciaram alterações no solo foram pH e os macronutrientes Mg, Al e SB, sendo os tratamentos orgânicos equivalentes e/ou melhores que os tratamentos convencionais. Para os parâmetros microbiológicos, o NMP de fungos apresentou os maiores valores nos tratamentos convencionais e controle. A produtividade agrícola não foi influenciada pelos diferentes tratamentos e insumos utilizados, independente da variedade de cana-de-açúcar utilizada. Por fim, foram observadas correlações positivas entre as variáveis CTC e quociente metabólico (qCO2) apontando potencial melhoria da qualidade do solo, com o emprego de insumos orgânicos

Patterns and Determinants of Off-Farm Migration: Transfer frictions and persistency of relative income gaps. Factor Markets Working Papers No. 36, February 2013

The inter-sectoral migration of agricultural labour is a complex but fundamental process of economic development largely affected by the growth of agricultural productivity and the evolution of the agricultural relative income gap. Theory and some recent anecdotal evidence suggest that as an effect of large fixed and sunk costs of out-farm migration, the productivity gap between the agricultural and non-agricultural sectors should behave non-monotonically or following a U-shaped evolution during economic development. Whether or not this relationship holds true across a sample of 38 developing and developed countries and across more than 200 EU regions was empirically tested. Results strongly confirm this relationship, which also emphasises the role played by national agricultural policy.

Klima und Landschaftsumgestaltung – Palynologische Hinweise zur Komplexität prähistorischer Mensch-Umwelt-Beziehungen

Pollen analytical studies of four radiocarbon dated sediment records from Switzerland suggest distinct phases of forest clearances and intensified land use from 1450–1250 BC, 650–450 BC, 50 BC–100 AD, and around 700 AD. These land use expansions coincided with periods of warm climate as recorded by Alpine dendroclimatic and Greenland oxygen isotope records. Our results suggest that harvest yields increased synchronously over wide areas of central and southern Europe during periods of warm and dry climate. Positive long-term trends in pollen values of Cerealia and Plantago lanceolata indicate that technical innovations during the Bronze and Iron Ages (e.g. metal ploughs, scythes, hay production, fertilizing methods) gradually increased agricultural productivity. However, our data imply that human societies were not able to compensate rapidly for harvest failures when the climate deteriorated. Agriculture in marginal areas was abandoned, and spontaneous reforestations took place on unoccupied land both north and south of the Alps.

Outlook '82 : proceedings /

Cover title.

Outlook '85 : proceedings.

Conference held Dec. 3-5, 1984.

Africa, the potential for higher food production : April 1985.

Cover title.

Outlook '87 : proceedings.

Conference held Dec. 2-4, 1986.

Land utilization and the farm problem /

"Issued November, 1930."

The 5th plate.

"December 1951".

Changes in farm production and efficiency.

Vol. for 1975 issued in Sept. 1976 is undated; vol. for 1976 issued Nov. 1976 is called 1977.

Seguridad alimentaria, nutrición y erradicación del hambre CELAC 2025: elementos para el debate y la cooperación regionales

La región de América Latina y el Caribe ha mostrado una trayectoria exitosa en el proceso de erradicación del hambre y es la única región del mundo que redujo a la mitad tanto la proporción de personas que padecen hambre (meta establecida en los Objetivos de Desarrollo del Milenio) como el número absoluto de personas afectadas por el hambre (meta establecida en la Cumbre Mundial sobre la Alimentación, de 1996). El propósito de esta publicación es suministrar a los países de la región información actualizada y oportuna sobre el estado de la seguridad alimentaria y nutricional, el papel que tienen distintas áreas como la agricultura, el comercio agroalimentario y la gestión de recursos naturales en la erradicación del hambre y la posibilidad de enfrentar con éxito la doble carga de la malnutrición, en un contexto en que los efectos del cambio climático pueden amenazar los avances observados hasta el momento en América Latina y el Caribe. El Plan para la Seguridad Alimentaria, Nutrición y Erradicación del Hambre de la CELAC 2025 es una herramienta trascendental para el logro de los Objetivos de Desarrollo Sostenible de la Agenda 2030 para el Desarrollo Sostenible y, por ello, alienta a los países de América Latina y el Caribe a redoblar los esfuerzos para identificar las áreas clave de política que permitan acelerar y consolidar el proceso de erradicación del hambre y hacer frente a la doble carga de la malnutrición en la región, donde el sobrepeso y la obesidad se suman cada vez más a ese flagelo.

Food and nutrition security and the eradication of hunger CELAC 2025: Furthering discussion and regional cooperation

The region of Latin America and the Caribbean can boast a successful track record in the process of eradicating hunger: it is the only region in the world that has halved both the proportion of people who suffer from hunger (the target set in the Millennium Development Goals) and their absolute number (the target set at the World Food Summit of 1996). This publication aims to provide the region’s countries with up-todate and timely information on the status of food and nutrition security; on the role in eradicating hunger played by the different areas such as agriculture, agrifood trade and natural resources management; and on the possibility of successfully addressing the twin burden of malnutrition, in a context where the effects of climate change could threaten the progress achieved in Latin America and the Caribbean thus far. The CELAC Plan for Food and Nutrition Security and the Eradication of Hunger 2025 is a cross-cutting tool for achieving the Sustainable Development Goals of the 2030 Agenda for Sustainable Development; and it thus encourages the countries of Latin America and the Caribbean to redouble their efforts to identify key policy areas that will make it possible to speed up and consolidate the process of eradicating hunger and tackle the twin burden of malnutrition in the region, in which overweight and obesity are increasingly adding to that scourge.